The high failure rates in mathematics courses have been a concerning matter in each semester at private universities. Studies about determining the causes of low mathematics achievement are very limited. The purpose of this study is to investigate the factors that affect low achievement in mathematics. In order to achieve this purpose, factor analysis was conducted to capture the potential factors which may affect achievement. Multiple linear regression was used to determine the factors that significantly affect the achievement in mathematics. A total of 111 students who enrolled in mathematics courses participated in the survey. This study revealed that one of the significant causes of low mathematics achievement is students’ educational background. Students who were not from science stream are at a disadvantage in achieving good performance in mathematics. Other factors of low mathematics achievement include race, age and students’ valuing of the importance of mathematics. One of the implications discussed in this paper is that mathematics educators must have several effective teaching strategies that suit students’ learning needs especially non-Chinese and older students. Such strategies might help educators achieve the desired learning outcomes and reduce failure rates.